Use of JMP® for High Explosive Formulation, Testing and Data Analysis
Paul Anderson
Until recently, the formulation of explosives was an iterative “one factor at a time” process. When considering the hazards involved in the handling, processing, and testing of these formulations, minimization of exposure to the explosive is of key importance. Often, because of the logistical separation between formulation and testing and the costs involved, there is little time and funding for maximum optimization. JMP Mixture design of experiments has proved to be a valuable tool in reducing the iterative process of testing and reformulation. The ability to predict a particular explosive characteristic is fairly well established with thermodynamic code. By utilizing a mixture design protocol and subsequent scripting in JMP, the design space of the formulation can be visualized with contour profilers and efficient trade-offs made prior to testing. The development of PAX-30, an explosive that combines both high blast and high metal pushing energy for fragmentation, will be shared. The explosive is unique in that it reduces the logistical needs of a soldier to possess multiple ammunition types for anti-personnel, through-wall, and anti-materiel targets. A DOE was undertaken so as to resolve the factors that contribute to early aluminum reaction in the detonation process. These factors include aluminum particle size, type of binder system, aluminum loading, and explosive loading. Detonation calorimetry in an inert atmosphere was used to assess the extent of aluminum reaction. A JMP script was developed to replace an old DOS-based program that analyzed cylinder wall velocity from cylinder expansion tests. Contour plots of the mixture DOE show excellent agreement with results, and further optimization of the formulation from the DOE resulted in more insensitivity with little or no loss in performance.